Moeini Behnam, Avval Tahereh G, Brongersma Hidde H, Průša Stanislav, Bábík Pavel, Vaníčková Elena, Strohmeier Brian R, Bell David S, Eggett Dennis, George Steven M, Linford Matthew R
Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA.
Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
Materials (Basel). 2023 Jun 29;16(13):4688. doi: 10.3390/ma16134688.
Delayed atomic layer deposition (ALD) of ZnO, i.e., area selective (AS)-ALD, was successfully achieved on silicon wafers (Si\SiO) terminated with tris(dimethylamino)methylsilane (TDMAMS). This resist molecule was deposited in a home-built, near-atmospheric pressure, flow-through, gas-phase reactor. TDMAMS had previously been shown to react with Si\SiO in a single cycle/reaction and to drastically reduce the number of silanols that remain at the surface. ZnO was deposited in a commercial ALD system using dimethylzinc (DMZ) as the zinc precursor and HO as the coreactant. Deposition of TDMAMS was confirmed by spectroscopic ellipsometry (SE), X-ray photoelectron spectroscopy (XPS), and wetting. ALD of ZnO, including its selectivity on TDMAMS-terminated Si\SiO (Si\SiO\TDMAMS), was confirmed by in situ multi-wavelength ellipsometry, ex situ SE, XPS, and/or high-sensitivity/low-energy ion scattering (HS-LEIS). The thermal stability of the TDMAMS resist layer, which is an important parameter for AS-ALD, was investigated by heating Si\SiO\TDMAMS in air and nitrogen at 330 °C. ALD of ZnO takes place more readily on Si\SiO\TDMAMS heated in the air than in N, suggesting greater damage to the surface heated in the air. To better understand the in situ ALD of ZnO on Si\SiO\TDMAMS and modified (thermally stressed) forms of it, the ellipsometry results were plotted as the normalized growth per cycle. Even one short pulse of TDMAMS effectively passivates Si\SiO. TDMAMS can be a useful, small-molecule inhibitor of ALD of ZnO on Si\SiO surfaces.
在以三（二甲基氨基）甲基硅烷（TDMAMS）终止的硅片（Si\SiO）上成功实现了氧化锌的延迟原子层沉积（ALD），即区域选择性（AS）-ALD。这种抗蚀剂分子沉积在一个自制的近大气压、流通式气相反应器中。此前已表明，TDMAMS在单个循环/反应中与Si\SiO发生反应，并大幅减少表面残留的硅醇数量。使用二甲基锌（DMZ）作为锌前驱体、HO作为共反应物，在商用ALD系统中沉积氧化锌。通过光谱椭偏仪（SE）、X射线光电子能谱（XPS）和润湿性确认了TDMAMS的沉积。通过原位多波长椭偏仪、非原位SE、XPS和/或高灵敏度/低能量离子散射（HS-LEIS）确认了氧化锌的ALD，包括其在TDMAMS终止的Si\SiO（Si\SiO\TDMAMS）上的选择性。通过在330°C的空气和氮气中加热Si\SiO\TDMAMS，研究了作为AS-ALD重要参数的TDMAMS抗蚀剂层的热稳定性。在空气中加热的Si\SiO\TDMAMS上比在氮气中更容易发生氧化锌的ALD，这表明在空气中加热的表面受到的损伤更大。为了更好地理解氧化锌在Si\SiO\TDMAMS及其改性（热应力）形式上的原位ALD，将椭偏仪结果绘制为每循环的归一化生长。即使是一个短脉冲的TDMAMS也能有效地钝化Si\SiO。TDMAMS可以成为Si\SiO表面氧化锌ALD的一种有用的小分子抑制剂。
